title: Development and validation of stability-indicating HPLC method for the simultaneous determination of paracetamol, tizanidine, and diclofenac in pharmaceuticals and human serum.
abstract: A method is described for the simultaneous determination of paracetamol, tizanidine, and diclofenac in mixtures. The method was based on HPLC separation of the three drugs followed by UV detection at 254 nm. The separation was carried out on a Hypersil ODS, C18 (250 x 4.6 mm id, 10 microm particle size) column using the mobile phase aqueous 0.2% ammonium carbonate-methanol (60 + 40, v/v) at a flow rate of 1 mL/min. The linear regression analysis data were used for the regression curve in the range of 170-10 000 ng/mL for paracetamol, 120-10 000 ng/mL for tizanidine, and 20-10 000 ng/mL for diclofenac. No chromatographic interference from tablet excipients was found. In order to check the selectivity of the proposed method, degradation studies were carried out using hydrolysis (acid, basic, and neutral), thermolysis, and oxidation. The developed method, after being validated in terms of precision, robustness, recovery, LOD, and LOQ, was successively applied to the analysis of pharmaceutical formulations and human serum.
authors.affiliation: University of Karachi, Department of Chemistry, Karachi-75270, Pakistan. farhanchemist@hotmail.com
authors.forename: Farhan Ahmed
authors.initials: FA
authors.lastname: Siddiqui
authors.forename: M Saeed
authors.initials: MS
authors.lastname: Arayne
authors.forename: Najma
authors.initials: N
authors.lastname: Sultana
authors.forename: Faiza
authors.initials: F
authors.lastname: Qureshi
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood*; D001774:Blood Chemical Analysis / Q000379:methods / Q000706:statistics & numerical data; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D003000:Clonidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000032:analysis / Q000097:blood; D004008:Diclofenac / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood*; D004355:Drug Stability; D006801:Humans; D006861:Hydrogen Peroxide; D016014:Linear Models; D055668:Photochemical Processes; D013056:Spectrophotometry, Ultraviolet; D013607:Tablets
chemical_list: D013607:Tablets; D004008:Diclofenac; D000082:Acetaminophen; C023754:tizanidine; D006861:Hydrogen Peroxide; D003000:Clonidine